Re: [PATCH 2/2] gpio: sim: simplify code with cleanup helpers

Re: [PATCH 2/2] gpio: sim: simplify code with cleanup helpers

[Dan Carpenter]

Hi Bartosz,

kernel test robot noticed the following build warnings:

https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Bartosz-Golaszewski/gpio-sim-simplify-code-with-cleanup-helpers/20230809-211601
base:   https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git gpio/for-next
patch link:    https://lore.kernel.org/r/20230809131442.25524-2-brgl%40bgdev.pl
patch subject: [PATCH 2/2] gpio: sim: simplify code with cleanup helpers
config: i386-randconfig-m021-20230809 (https://download.01.org/0day-ci/archive/20230811/202308110253.R2TUMfFr-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce: (https://download.01.org/0day-ci/archive/20230811/202308110253.R2TUMfFr-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
| Closes: https://lore.kernel.org/r/202308110253.R2TUMfFr-lkp@intel.com/

smatch warnings:
drivers/gpio/gpio-sim.c:1472 gpio_sim_config_make_device_group() warn: possible memory leak of 'dev'

vim +/dev +1472 drivers/gpio/gpio-sim.c

cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1460  static struct config_group *
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1461  gpio_sim_config_make_device_group(struct config_group *group, const char *name)
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1462  {
c7a663cdcfc698 Bartosz Golaszewski 2023-08-09  1463  	struct gpio_sim_device *dev __free(kfree) = NULL;
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1464  	int id;
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1465  
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1466  	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1467  	if (!dev)
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1468  		return ERR_PTR(-ENOMEM);
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1469  
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1470  	id = ida_alloc(&gpio_sim_ida, GFP_KERNEL);
c7a663cdcfc698 Bartosz Golaszewski 2023-08-09  1471  	if (id < 0)
cb8c474e79be45 Bartosz Golaszewski 2021-12-07 @1472  		return ERR_PTR(id);

kfree(dev);

cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1473  
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1474  	config_group_init_type_name(&dev->group, name,
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1475  				    &gpio_sim_device_config_group_type);
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1476  	dev->id = id;
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1477  	mutex_init(&dev->lock);
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1478  	INIT_LIST_HEAD(&dev->bank_list);
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1479  
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1480  	dev->bus_notifier.notifier_call = gpio_sim_bus_notifier_call;
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1481  	init_completion(&dev->probe_completion);
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1482  
c7a663cdcfc698 Bartosz Golaszewski 2023-08-09  1483  	return &no_free_ptr(dev)->group;
cb8c474e79be45 Bartosz Golaszewski 2021-12-07  1484  }

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH 2/2] gpio: sim: simplify code with cleanup helpers

[Andy Shevchenko]

On Fri, Aug 11, 2023 at 08:20:11AM +0300, Dan Carpenter wrote:

> smatch warnings:
> drivers/gpio/gpio-sim.c:1472 gpio_sim_config_make_device_group() warn: possible memory leak of 'dev'

Isn't smatch a bit dumb about cleanup.h?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 2/2] gpio: sim: simplify code with cleanup helpers

[Dan Carpenter]

On Fri, Aug 11, 2023 at 12:14:52PM +0300, Andy Shevchenko wrote:
> On Fri, Aug 11, 2023 at 08:20:11AM +0300, Dan Carpenter wrote:
> 
> > smatch warnings:
> > drivers/gpio/gpio-sim.c:1472 gpio_sim_config_make_device_group() warn: possible memory leak of 'dev'
> 
> Isn't smatch a bit dumb about cleanup.h?
> 

Aw.  Crud.  I hadn't seen that this was a cleanup.h thing.

I did do some work to suppoort cleanup.h but probably it will take a
while to work out the kinks.  Let me figure this out.

regards,
dan carpenter